It’s the elephant in the room. Yes, Meta Knight has been nerfed.
From the beginning, Meta Knight has only be weakened in very specific areas. Shuttle Loop is still invincible but no longer a real KO move. Mach Tornado is just as safe but spits enemies out so that it is less rewarding to spam. Finally, down smash is a little weaker.
That’s it. Meta Knight even got a small buff of his own: Preventing the Infinite Dimensional Cape exploit actually lets him use the attack faster! He is still a nightmare when played by an expert; anyone who expects Meta Knight to be somehow weak in Balanced Brawl can expect to be very, very wrong.
Balanced Brawl Bonus: Dimensional Cape Cancel
Meta Knight can cancel his Dimensional Cape at any time by flicking the c-stick. This strike is more powerful than the old Dimensional Cape attack.
Other Major Changes
Mach Tornado now hits opponents outward and does not knock down, generally far less abusive.
Shuttle Loop now does less damage and far less knockback.